ELECTRONIC STRIP YARN
Electronic devices (4, 24) are mounted in sequence or series along a plurality of laterally spaced discrete lines (10) on a sheet of non-conductive flexible planar support material (50); and the sheet is slit or stripped between said lines to create at least two yarns each in the form of a strip bearing a series of said devices. The width of each strip can be substantially the same as that of the mounted device or devices; normally less than twice that of the device or devices. The support material can be in the form of a continuous length passing through a mounting station (54), and on which series of the electronic devices are mounted in said lines substantially parallel to the direction of passage of the material. The material bearing the devices can be slit into strips directly, or wound onto a roll (64) for subsequent division into strips The material may be formed with lines of weakness (14) to facilitate slitting into strips. The thickness of the support material is normally no more than IO μm, and with the width of the devices typically being no more than 800 nm, a strip bearing the devices can thus be used as a yarn or strip for use in many applications, both functional and decorative, either alone or within a sleeve.
This invention relates to the manufacture of yarns incorporating electronic devices. It has particular application to such yarns in which the devices and electrical connections thereto are protected. A preferred use of the yarns is incorporation into fabric products for example, although other uses are contemplated.
International Patent Publication Nos. WO2006/123133 and WO2011/010093, the contents whereof are hereby incorporated by reference, disclose multi-filament yarns including an operative devices confined between the yarn filaments, and a method for its manufacture. The filaments of the yarns disclosed may be textile fibres such as polyester, polyethylene, polypropylene or polyamide. One or more of the yarn filaments could be electrically conductive and coupled to a confined device to form an electrical connection thereto. These filaments can be fine metal filament wires or in the form of a polymeric monofilament yarn plated with a thin film of either copper, nickel, gold or silver. The device or devices may take any of various forms, such as a silicone chip, a ferro-magnetic polymeric chip or a phase change chip.
Reference is also directed to Japanese Patent specification No. 2013189718A and US Patent publication No. 2013/092742, the disclosures whereof are hereby incorporated. Both describe yarns carrying electronic devices within a protective outer layer or sheath. Yarns of the above International Publication are effective and can be used in fabric products. However, where the device has an electrical connection the connection will be exposed on the yarn surface and thereby compromised by contact with other yarns or elements, or by external conditions. The Japanese and US references go some way towards addressing this issue, but do not provide a resolution.
In our International Patent Application published under No. W02016/038342 (hereinafter referred to as “our International Application”), the disclosure whereof is also hereby incorporated by reference we disclose an electronically functional yarn comprising a plurality of carrier fibres forming a core; a series of electronic devices mounted on the core with conductive interconnects extending along the core; a plurality of packing fibres around the core, the devices and the interconnects; and a retaining sleeve around the packing fibres, wherein the core, the devices and the interconnects are confined within the plurality of packing fibres retained in the sleeve. The interconnects can comprise at least one conductor that extends the length of the yarn. By mounting the devices and interconnects on carrier fibres they are more easily retained in the body of the yarn and within the packing fibres.
The present invention is also directed at the use of carriers bearing mounted electronic devices for use as a yarn or in yarns of the kind described in the Patent publications referred to above. Particularly it is directed at the manufacture of such yarns or filament fibres. According to the present invention electronic devices are mounted in sequence or series along a plurality of laterally spaced discrete lines on a sheet of non-conductive flexible planar support material; and the sheet is slit or stripped between said lines to create at least two yarns or filament fibres each in the form of a strip bearing a series of said devices. The width of each strip can be substantially the same as that of the mounted device or devices; normally less than twice that of the device or devices. Thus, with the thickness of the support material being normally no more than 10 μm, and with the width of the devices typically being no more than 800 μm, a strip bearing the devices can thus be used as a yarn or strip for use in many applications, both functional and decorative, either alone or within a sleeve.
The support material can be provided in the form of a continuous length which is drawn through a mounting station where the series of electronic devices are installed in discrete lines substantially parallel to the direction of passage of the material. The drawn material can then be rewound onto a roll for subsequent slitting or stripping, or passed directly to a cutting device in which it is divided into the strips. Lines of weakness may be formed between the lines of devices to facilitate subsequent slitting or stripping if the material is not to be slit or stripped directly after the electronic devices have been mounted. The support material will normally itself be drawn as a tape from a roll, but might be delivered from another source; for example, directly from its own manufacture.
Yarns or filament fibres in the form of strips made according to the invention can be supplemented with means such as buttons; buttonholes; hooks or eyes, for attaching it to another surface or body. Where there are a plurality of devices on the length of material, they will normally be mounted on the same side. This arrangement means that the opposite side can for example, bear an adhesive enabling the strip to be readily attached to another surface. In some embodiments, the planar material may be coated with a conductive material on its face opposite the face upon which the devices are mounted. Such a layer may itself be in the form of a separate sheet, strip or multiple strips. However, devices may of course be mounted on both sides of the material, and this can facilitate the mounting process when different forms of device are being used.
The planar support material used in the invention is thin (typically 2.0-7.0 μm thick), and preferred materials are polymer sheet or tape, typically polyester. Other options are polyamides, polyethylene, polyetheretherketone (PEEK), poly-oxydiphenylene-pyromellitimide (Kapton),Polybenzimidazole or aramid based materials. The material should have a high melting point, typically above 350° C., and have a high level of thermal and chemical stability. The reason for this is to ensure it can withstand the heat generated when interconnects are coupled to the electronic devices.
The strips with electronic devices mounted thereon made according to the invention can be used alone, or as the basis for a yarn or filament fibre in which the strip (bearing the devices) is enclosed in a sleeve. Such a yarn or fibre may be incorporated in a fabric. In one example, the strip may form the core in a yarn of the kind described in our International Application. In such an embodiment the packing fibres can be untwisted; i.e. extend generally parallel to the yarn axis, but may be selectively bunched or twisted to fill spaces between the devices. A separate filler material may also be used for this purpose. These options can serve to preserve a substantially uniform cross-section along the length of the yarn and between the devices. The packing fibres, and a filler material if used, may be selected to either encourage or discourage the absorption of moisture by the composite yarn.
The electronic devices incorporated in yarns embodying the invention can take many forms, including operative devices such as a silicon chip signaling devices; light, sound or symbol generators; micro-controllers and energy harvesting devices. Particularly suitable for use in yarns of the present invention are ultra thin electronic dice. The present invention is also suitable for radio frequency identification devices (RFIDs) with antennas extending along the length of material on both sides of the RFID chip. Such antennas, or interconnects coupled to the devices can be mounted on the material before the devices, such as by digital printing, and the devices then mounted thereover.
The invention will now be described by way of example and with reference to the accompanying schematic drawings wherein:
The length of non-conductive planar material shown in
If desired, a strip of the kind described above can be supplemented with means for attaching it to another body or surface as part of the manufacturing or assembly process. Possibly most simply, when devices are mounted on one side of the planar material, a layer of adhesive can be applied to the other. The strip with the devices uppermost can then be easily secured on a surface for identification or ornamental purposes. Other forms of attachment, such as buttons; buttonholes; hooks, and eyes, can also be fitted to match complementary forms on the other body or surface. Such supplementation can be accomplished on separated strips or on a sheet or continuous length of the planar material before or after the devices are mounted thereon.
The drawings show the mounted electronic devices quite closely spaced in their respective series or sequences on the support material. It will though, be appreciated that this spacing can of course be selected according to the intended ultimate use of the resulting strip or yarn. If the yarn is to be used in a fabric the distances between devices along the yarn can be quite large, and selected to locate respective devices in the fabric.
As noted above, devices that might be used in the practice of the invention typically have a width up to 800 μm, normally at least 100 μm. Some chips have a width of around 400 μm, but smaller dimensions are possible. Normally, the devices will be arranged in straight lines to facilitate slitting or otherwise dividing the sheet into strips, but it will be appreciated that shaped lines can easily be created and cut. One product of the process is a sheet bearing the arranged lines of devices as shown in
The cutting device may be replaced by a scoring device creating lines of weakness which results in the material leaving in the form of a tape which can be readily torn into strips. Each strip can then itself be used as a yarn or filament fibre for use in fabrics for example, in which the electronic devices can function, or lengths thereof can be used as attachments to products for identification or other purposes. They can also be used in the formation of a composite yarn of the kind described above with reference to
Claims
1. A method of manufacturing carriers, each having at least one filament fibre and a plurality of electronic devices, said method comprising the steps of mounting said devices in series along a plurality of laterally spaced discrete lines on a sheet of non-conductive flexible planar support material; and stripping the sheet between said lines to create at least two carriers, each in the form of a strip bearing a series of said devices, the width of the strip being no more than twice that of one of the devices.
2. A method according to claim 1 wherein the sheet of non-conductive flexible planar support material is in the form of a continuous length passing through a mounting station, and on which series of the electronic devices are mounted in said lines substantially parallel to the direction of passage of the sheet of non-conductive flexible planar support material.
3. A method of claim 2 wherein the sheet of non-conductive flexible planar support material is drawn from a roll.
4. A method of claim 3 wherein the electronic devices are mounted on the sheet of non-conductive flexible planar support material prior to formation of said sheet into a roll.
5. A method of claim 1 wherein the sheet of non-conductive flexible planar support material is formed with lines of weakness between the lines of devices to facilitate stripping the sheet of non-conductive flexible planar support material therebetween.
6. A method of claim 1 wherein the devices are mounted on the sheet by means of adhesive.
7. A method of claim 1 wherein the devices include conductive interconnects connected thereto and oriented to extend along each strip in opposite directions from each device.
8. A method of claim 7 wherein the interconnects are mounted on the sheet of non-conductive flexible planar support material prior to mounting of the devices thereover.
9. A method of claim 8 wherein the interconnects are printed on a surface of the sheet of non-conductive flexible planar support material.
10. A method of claim 7 wherein the conductive interconnects are antennas.
11. A method according of claim 7 wherein the connection of the interconnects to each device is between the device and the sheet, of non-conductive flexible planar support material.
12. A method of claim 1 wherein the sheet of non-conductive flexible planar support material is made from a group consisting of polyester; polyetheretherketone (PEEK); and poly-oxydiphenylene-pyromellitimide (Kapton).
13. A method of claim 1 further including the steps of feeding at least one strip bearing the devices centrally through a channel with packing fibres around the sides thereof to form a fibre assembly around the strip; feeding the fibre assembly into a sleeve forming unit in which a sleeve is formed around the assembly to form a composite yarn; and withdrawing the composite yarn from the sleeve forming unit.
14. An assembly comprising a sheet of flexible non-conductive planar material having a length; and a plurality of electronic devices mounted to the sheet and arranged in series to define a plurality of lines of devices extending along the length of the sheet of flexible non-conductive planar material, wherein the spacing between devices in adjacent lines is no more than the width of the widest device in a respective line, and wherein said assembly is in the form of a roll.
15. The assembly of claim 14 wherein the sheet of flexible non-conductive planar material is formed with lines of weakness between the lines of devices to facilitate dividing the sheet into strips of devices mounted on the sheet.
16. The assembly of claim 14 wherein conductive interconnects extend in opposite directions from each device along the respective lines.
17. The assembly of claim 16 wherein the interconnects comprise antennas.
18. The assembly of claim 14 wherein the electronic devices are each separately selected from a group consisting of: silicon chip signaling devices; light, sound or symbol generators; micro-controllers; energy harvesting devices; and radio frequency identification devices (RFIDs).
19. An electronically functional carrier comprising a strip of electronically non-conductive flexible planar material with a plurality of electronic devices mounted thereon, wherein the width of the strip is no more than twice the width of the widest of the devices, wherein said strip bearing the devices has been stripped from a length of said material bearing sequences of said electronic devices in spaced lines thereon.
20. The electronically functional carrier of claim 19 wherein conductive interconnects extend along the strip in opposite directions from each device.
21. The electronically functional carrier of claim 20 wherein the interconnects comprise antennas.
22. The electronically functional carrier of claim 19 wherein the strip has first and second opposing sides and the electronic devices are all mounted on the first side of the strip.
23. The electronically functional carrier of claim 22 wherein the second side of the strip bears an adhesive.
24. The electronically functional carrier of claim 19 further including means for attaching the strip to another body.
25. The electronically functional carrier of claim 19 wherein each device is enclosed in a protective polymeric micro pod.
26. The electronically functional carrier of claim 19 wherein the strip is made from a material selected from a group consisting of polyester; polyetheretherketone (PEEK); and poly-oxydiphenylene-pyromellitimide (Kapton).
27. The electronically functional carrier of claim 19 wherein the electronic devices are each separately selected from a group consisting of: silicon chip signaling devices; light, sound or symbol generators; microcontrollers; energy harvesting devices; and radio frequency identification devices (RFIDs).
28. The electronically functional carrier of claim 19 wherein a plurality of packing fibres are disposed around the strip and devices; and a retaining sleeve is disposed around the packing fibres, wherein the strip and devices are confined within the plurality of packing fibres retained in the sleeve to form a composite yarn.
Type: Application
Filed: Dec 23, 2016
Publication Date: Jan 3, 2019
Patent Grant number: 10458048
Inventor: Tilak Kithsiri Dias (Nottingham)
Application Number: 16/066,715